Early in her career, Virginia M. Rometty, I.B.M.'s next chief executive, was offered a big job, but she felt she did not have enough experience. So she told the recruiter she needed time to think about it.
That night, her husband asked her,"'Do you think a man would have ever answered...

Business model innovation is the new strategic imperative—by now, this is becoming more generally acknowledged. But companies routinely fail at self-reinvention because they are so busy pedaling the bicycle of their current business models they leave no time, attention, or resources to design, prototype, and test new ones.